title: Repairing ditched amalgam restorations is less time and tooth structure-consuming than replacement.
abstract: OBJECTIVE
  To evaluate the dental structure loss associated with procedures of replacement or maintenance for ditched amalgam restorations in primary molars and the time required to perform each treatment.
  
  
  METHODS
  Ditched amalgam restorations (n = 40) were submitted to four different strategies: polishing group-polishing and finishing of restorations; amalgam group-replacement of ditched amalgam restorations with new amalgam restorations; resin group-replacement of amalgam restorations with resin composite restorations; flowable resin group-filling the ditch with a flowable resin composite. The teeth were analysed with a stereomicroscope and the areas pre- and post-treatment were determined by image analysis software to evaluate structural loss. The time required to perform each treatment was recorded in seconds.
  
  
  METHODS
  Student's t test was used to compare areas pre- and post-treatments. ANOVA and Student-Newman-Keuls tests (p < 0.05) were used to compare differences among groups and the time to perform each procedure.
  
  
  RESULTS
  Dental structure loss was observed in resin and amalgam groups. Replacing the restorations with amalgam took more time, while polishing and applying flowable resin composite consumed less than half of the time compared with amalgam and resin groups.
  
  
  CONCLUSIONS
  Maintenance of ditched amalgam restorations by polishing and sealing preserves dental structure and involves less time compared with that for replacement of restorations.
authors.affiliation: Department of Orthodontics and Paediatric Dentistry, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes, 2227-Cidade Universitária, São Paulo, SP, 05508-000, Brazil.
authors.forename: T L
authors.initials: TL
authors.lastname: Lenzi
authors.forename: M
authors.initials: M
authors.lastname: Marquezan
authors.forename: G C
authors.initials: GC
authors.lastname: Bonini
authors.forename: L B
authors.initials: LB
authors.lastname: Camargo
authors.forename: D P
authors.initials: DP
authors.lastname: Raggio
mesh_terms: D003723:Dental Amalgam; D003793:Dental Restoration, Permanent; D006801:Humans; D008963:Molar; D014094:Tooth, Deciduous
chemical_list: D003723:Dental Amalgam